The present invention relates to control for an appliance that a user manipulates and particularly relates to a technology for appliance control utilizing user's biological signal such as an electroencephalogram (EEG).
Of conventional techniques for appliance control utilizing a biological signal such as an electroencephalogram, there is a technique utilizing a beta wave (12 to 25 Hz), which is a frequency component of an electroencephalogram capable of being generated intentionally and voluntarily. In this technique, software switches (menu items) to which intention to be conveyed (for example, nurse call, drink, and the like), which are expressed in the form of letter or figure, are allotted are displayed in matrix on a display or the like for presentation to a user and each software switch is highlighted sequentially at predetermined time intervals. When a menu item that a user desires is highlighted, the user selects the menu item by generating the beta wave. This enables a user incapable of conveying his/her intention through language and body gesture to convey his/her intention to the others.
On the other hand, in cognitive psychology and clinical medical science, study employing physiological indexes such as an electroencephalogram and the like has progressed. For example, diagnoses of dementia, melancholia, schizophrenia, hyperactive disorder, and the like and effectiveness judgments of various medicine and rehabilitation are carried out using electroencephalographs.
However, in the aforementioned conventional techniques, the timing that the beta wave should be generated may shift or the beta wave may be generated according to a physical state, unintentional motion, or the like at a timing different from user's intention. In these cases, the user cannot convey his/her intention correctly and cannot manipulate the appliance as desired. Further, it is already known that rather patience is required for acquiring the technique of generating the beta wave. Thus, the beta wave is not necessarily appropriate for controlling an appliance.